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The Miller-Urey experiment was the first attempt to scientifically explore ideas about the origin of life. Stanley Miller simulated conditions thought be common on the ancient Earth. The purpose was to test the idea that the complex molecules of life (in this case, amino acids) could have arisen on our young planet through simple, natural chemical reactions. The experiment was a success in that amino acids, the building blocks of life, were produced during the simulation. The finding was so significant that it kick started an entirely new field of study: Prebiotic Chemistry. Scientists now have reason to believe that the gases used in the Miller-Urey simulation were not actually the same as those of the ancient atmosphere. Because of this, many experiments have since been done, testing a wide variety of atmospheres and different environmental conditions. The results are overwhelming: the molecules of life can form under a wide variety of ancient Earth-like conditions. Many questions about the origin of life remain to be answered but these findings give strong support to the idea that the first living cells on Earth may have emerged from natural chemical reactions.

This interrupted case study examines basic concepts of chemical bonding by telling the story of "Madison," a young girl eager to learn how her hair can transition from natural curls to straight, smooth tresses. The case can be used to teach or review the major categories of bonds (ionic, covalent and hydrogen), major macromolecules of life, and hydrolytic and dehydration reactions. It also explores how chemical relaxers and heat through blow drying and flat-ironing can change the nature of straight, wavy and curly hair through the disruption of protein shape. Students will thus learn what it means when a protein has become denatured and how various variables such as pH, heat and salts can lead to the unraveling of the three-dimensional shape of proteins. This case is suitable for an AP high school course, or for an introductory biology or chemistry course for majors or non-majors. This activity can also be used as a review of basic biology and chemistry for students in an upper-level biochemistry course.

This case study presents the story of "Nick," a student who has been assigned the task of writing a research paper describing the fundamentals of chemical bonds and how they relate to human life. When Nick experiences difficulty remembering information about the different types of chemical bonds, he turns to his tutor, Josh, for help. Josh explains orbitals and valence electrons to Nick, and then they together review nonpolar and polar covalent bonds, ionic bonds, and hydrogen bonds. A final practical application exercise requires that students write about how different types of chemical bonds may relate to the development of Alzheimer's disease and to the mechanism of action of potential drug treatments.  The case is presented with PowerPoint slides and is designed to be used with a personal response system ("clickers"), but students can instead record their answers on paper or share them verbally.  The content is appropriate for use in high school and undergraduate introductory chemistry and biology courses.

It's an inevitable side effect of longevity: your hair will turn gray. In this episode, Sophia Cai chats about the chemistry of your natural hair color, why it eventually turns white, and how scientists may be able to slow that graying down.

To understand the importance of elements to nutrition. Of the approximately 115 elements known, only the 19 highlighted in purple in Figure 1.26 are absolutely required in the human diet. These elements-called essential elements-are restricted to the first four rows of the periodic table (see Chapter 32 "Appendix H: Periodic Table of Elements"), with only two or three exceptions (molybdenum, iodine, and possibly tin in the fifth row). Some other elements are essential for specific organisms. For example, boron is required for the growth of certain plants, bromine is widely distributed in marine organisms, and tungsten is necessary for some microorganisms.

TED_Ed videos Chemistry play list

Student curated websites on biomolecules and chemistry of life

You have probably had the burning sensation of eating a jalapeno or other tear-inducing pepper. What causes this painful fire in your mouth? The short answer is capsaicin. But what exactly is capsaicin? How does it work? Why do people drink milk to relieve the pain? Reactions has the chemistry to answer all of these sizzling questions.

Origin of life - volcanic pools - ocean floor - outer space

Common in cuisine all around the globe, onions are renowned for their ability to make us all look like cry babies. In Reactions' latest video, we get to the bottom of this teary phenomenon and reveal exactly what chemical mechanisms trigger it. The video also features a few chemistry-backed tips you can try at home to stop the tears before they start.

Origins of life with self-replicating molecules

Post the link to the Science News article "Life on Earth may have begun in hostile hot springs" to your virtual classroom. Ask students to read the article for homework and prepare for online class by answering the first question. Before the class meets, provide the students with the links to all articles they will need for class. Class discussion can be conducted via Zoom; the research and recipe-building components can be conducted in breakout rooms.

Published on Oct 14, 2015 7:50  If you take a look at an ingredients list, odds are you'll find natural and artificial flavors somewhere in there. Turns out there's a whole science to making your pumpkin spice latte taste like pumpkin spice, or your potato chips taste like pizza.

3:35 video Enzymes are the critical ingredient in every organism that make life possible. They are catalysts and drive every chemical reaction that takes place in the human body, enabling our bodies to be built from proteins, carbohydrates, and fats. In this program from VEA we investigate the role of enzymes in detail, offering both theoretical and practical examples.

How do we know what matter is made of? The quest for the atom has been a long one, beginning 2,400 years ago with the work of a Greek philosopher and later continued by a Quaker and a few Nobel Prize-winning scientists. Theresa Doud details the history of atomic theory.

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In order to be useful in treating human infections, antibiotics must selectively target bacteria for eradication and not the cells of its human host. Indeed, modern antibiotics act either on processes that are unique to bacteria--such as the synthesis of cell walls or folic acid--or on bacterium-specific targets within processes that are common to both bacterium and human cells, including protein or DNA replication. Following are some examples.

As the narrative goes, fat is bad. Well, it's actually more nuanced than that. The type of fat you eat is more impactful on your health than the quantity. George Zaidan examines triglycerides, the varied molecules that make up fat, and how to identify which types of fat you are consuming.

Would you rather be bitten by a venomous rattlesnake or touch a poisonous dart frog? While both of these animals are capable of doing some serious damage to the human body, they deliver their dangerous toxins in different ways. Rose Eveleth sheds light on the distinction between poison and venom (and why you shouldn't treat either one like you've seen in the movies).

3:47 video: Vinegar may have a powerful smell, but did you know it's actually a weak acid? In the chemical economy, acids actively give away their protons while bases actively collect them -- but some more aggressively than others. George Zaidan and Charles Morton use the currency of subatomic particles to explain this unseen exchange.